CAR-T Cell Therapy in Cancer: Tribulations and Road Ahead

Figure 1

The development and design principle of CAR-T three generations. The first generation of CAR-T cells was composed of immunoglobulin scFv and CD3 complexes. Most of the experiments did not respond well in cell expansion, in vivo survival time, cytokine secretion, etc., and the therapeutic effect was not as expected. The second- and third-generation CARs add costimulatory molecules such as CD28, CD134, and CD137 (4-1BB) to the chimeric receptor, which enables the cells to obtain long-lasting in vitro proliferation ability and strong cytokine secretion ability. The fourth generation of CAR-T can solve the problem that traditional CAR-T cannot identify and remove some antigens that are not explicitly recognized by T cells.